利用发根农杆菌转化实美橙子叶外植体的研究

TRANSFORMATION OF COTYLEDON EXPLANTS OF CITRUS SINENSIS L.WITH AGROBACTERIUM RHIZOGENES

以过夜培养的发根农杆菌 R_(1000)、15834、A)4感染实美橙子叶外植体,与菌体共培养3天后,转移至含头孢霉素的无激素 MT 培养基上进行选择培养,10天后开始产生毛状根,转化率为23%～36%。毛状根在继代培养中,稳定地保持激素自主性生长的特性.纸电泳检测证明,毛状根中含有甘露碱和农杆碱,表明发根农杆菌 Ri 质粒的 T-DNA 转移并整合入实美橙子叶细胞核基因组中,得到了表达,部分毛状根已分化产生不定芽和苗.

Wounded and precultured cotyledon explants of Citrus sinensis (L).Osbesk were in- fected with the wild type strains of Agrobacterium rhizogenes (A_4,R_(1000) and 15834), which were at the logarithmic growth phase.The infected explants were cultured under weak light on an MS medium without any hormones.Transformed roots were produced af- ter 10-day culture.The frequency of the transformed explants by A.rhizogenes was esti- mated ca.23%～36%,The transformed roots were identified by their ability to proliferate roots on hormone-free media and to contain agropine and mannopine in their tissues.The results indicated that the T-DNA of Ri plasmid in A.rhizogenes was successfully transferred and integrated into the nuclear genome of C.sinensis and got ex- pressed.Some buds were regenerated from the transformed roots.